Lamp control means



Sept. 13, 1966 I. MINDELL LAMP CONTROL MEANS Filed May 4, 1965 INVENTOR. MARVIN LMINDELL United States Patent 3,272,967 LAMP CONTROL MEANS Marvin I. Mindell, Great Neck, N.Y., assignor to Viewlex, Inc, Holbrook, N.Y. Filed May 4, 1965, Ser. No. 453,045 4 Claims. (Cl. 219-471) This invention relates to lamp control means and more particularly to means for controlling a heat lamp of the type used in a dry copy machine.

Machines of this type generally use a very intense heat lamp mounted inside a glass pressure roller which is focused on the line of tangency of two pressure rollers between which the papers are passed.

It for any reason the main pressure roller stops rotating while the exposure lamp is on, the rubber material of the pressure roller will start to deform and discolor due to the intense heat at the point on the roller where the lamp is focused. This will permanently damage the roller. If some copy material is in the machine, it will start to burn at this point. There are many reasons for this roller to cease turning all of which occur only under extenuating circumstances. Among these are paper jamming, a damage drive belt, a damaged motor, or electronic motor drive circuit. In order to prevent the lamp from turning on in the event that the main pressure roller ceases to turn the present invention has been developed.

Accordingly, a principal object of this invention is to provide new and improved lamp control means.

Another object of the invention is to provide new and improved heat lamp control means.

Another object of the invention is to provide new and improved heat lamp control means for a dry copy machine.

Another object of the invention is to provide new and improved heat lamp control means for a dry copy machine which is arranged so that the lamp will be de-energized if the rollers stop turning for any reason.

Another object of the invention is to provide new and improved apparatus having a heat lamp of the type directing heat onto papers passed between two rollers, means to apply voltage to said lamp only while said rollers are rotating comprising, a solenoid, a lamp switch connected in series with said lamp and a source of power, said switch being normally open but being adapted to be closed by said solenoid, means to apply voltage across said solenoid for a time slightly greater than one rotation of said rollers and means operated by said rollers to reactivate said voltage applying means once each cycle of said rollers.

These and other objects of the invention will he apparent from the following specification and drawings of which:

FIGURE 1 is a perspective view of an embodiment of the invention.

FIGURE 2 is a schematic circuit diagram.

Referring to the figures, the rollers 1 and 2 are pressure rollers and the papers, both the original and the copy paper, are passed between them. The roller 2 is a hollow glass roller and contains a heat lamp L which is generally of the type having a reflector so that the heat is focused on the line of tangency between the two rollers. If the two rollers should become jammed or stop for any reason, it is necessary that the lamp be turned off immediately to avoid damage to the papers and to the rollers.

The present invention accomplishes this by providing a cam operated switch which is connected to charge a condenser to maintain a voltage across a solenoid which is connected to hold the lamp switch closed. If for any reason, the roller stops rotating, the condenser will discharge and the lamp switch will be opened. More specifically, referring to FIGURE 2, the blade 5 of the switch ice 4 is connected in series with the condenser C1. When the blade 5 makes contact with the contact A, then the condenser C1 is connected across the source of power via the rectifier 12 and the filter condenser 15.

When the blade 5 makes contact with the contact C, then the condenser C1 is connected across in series with the condenser C2 and condenser C2 is connected across the solenoid R1.

The operation of the circuit is as follows:

As the main pressure roller 1 rotates, a cam 3 on the same shaft also rotates. This cam actuates a switch 4 swinging the arm 5 of the switch first from one fixed. contact then to the other. The arm always disconnects from one contact before contacting the other. The circuit is arranged so that when the switch arm 5 is on contact A, condenser or capacitor C1 charges up. Then as the cam rotates, the arm 5 leaves contact A and contacts contact C charging condenser or capacitor C2 and pulling in solenoid R1 closing the relay contacts 10 in series with the lamp. The lamp is now connected to the line and is able to operate normally, that is, the lamp goes on when the paper sensing switch'll is energized. The time constant of condenser C2 and the resistance of the coil of the relay solenoid R1, is calculated so that solenoid R1 remains energized long enough to all-ow for one full rotation of the cam at the slowest exposure speed of the rollers. However, if for any reason the cam stops rotating, it can be seen that condenser C2 will discharge allowing solenoid R1 to open, disconnecting the lamp from the line. Condenser 15 may be used in order to provide filtering and resistors may be interposed in series with the diode on any or all of the condensers to limit the charging current surge.

Many modifications may be made by those who desire to practice the invention without departing from the scope thereof Which is defined by the following claims:

I claim:

1. In apparatus having a heat lamp of the type directing heat onto papers passed between two rollers,

means to apply voltage to said lamp only while said rollers are rotating comprising:

a solenoid,

a lamp switch connected in series with said lamp and a source of power,

said switch being normally open but being adapted to be closed by said solenoid,

means to apply voltage across said solenoid for a time slightly greater than one rotation of said rollers, and

means operated by said rollers to reactivate said voltage applying means once each cycle of said rollers.

2. In apparatus having a heat lamp of the type directing heat onto papers passed between two rollers,

means to apply voltage to said lamp only while said rollers are rotating comprising:

a cam mounted on one of said rollers,

a first switch adapted to be closed by said cam,

a first condenser connected in series with the blade of said switch,

a second condenser connected to one contact of said switch,

a solenoid connected in parallel with said second condenser,

a lamp switch connected in series with said lamp and a source of power,

said switch being normally open but being adapted to be closed by said solenoid,

the time constant of said solenoid and said second condenser being chosen so that said solenoid will remain energized for slightly longer than one rotation of said roller.

- 3,272,967 3 4 3. In apparatus having a heat lamp of the type directa second capacitor connected to one pole of said ing heat onto papers passed between two rollers, switch,

means to apply voltage to said lamp only while said a source of power connected to one of the other rollers are rotating comprising:

noid for a time slightly greater than one rotation of said rollers at their lowest speed, and means operated by said rollers to recharge said poles of said switch,

a solenoid, 5 a solenoid connected in parallel with said second a lamp switch connected in series with said lam capacitor, and a source of power, a lamp switch connected in series with said lamp said switch being normally open but being adapted and a source of power,

to be closed by said solenoid, said switch being normally open but being adapted capacitor means to apply voltage across said soleto be closed by said solenoid,

the time constant of said solenoid and said second capacitor being chosen so that said solenoid will remain energized 'for one rotation of said roller.

said voltage applying capacitor means once each cycle. 4. In apparatus having a heat lamp of the type directing heat onto papers passed between two rollers,

References Cited by the Examiner UNITED STATES PATENTS to to lamp $222 222 54122: a;::::s:aa;;;; 2221:: mtatmg mmpnsmg: 3,100,252 8/1963 Shaler et al. 219 471 a cam mounted on one of said rollers, 3 164 717 1/1965 Kaufman 219 519 a double pole switch having a blade,

said cam being connected to move said blade from one pole to the other,

a first capacitor connected in series with the blade of said switch,

RICHARD M. WOOD, Primary Examiner.

ANTHONY BARTIS, Examiner.

L. H. BENDER, Assistant Examiner. 

1. IN APPARATUS HAVING A HEAT LAMP OF THE TYPE DIRECTING HEAT ONTO PAPERS PASSED BETWEEN TWO ROLLERS, MEANS TO APPLY VOLTAGE TO SAID LAMP ONLY WHILE SAID ROLLERS ARE ROTATING COMPRISING; A SOLENOID, A LAMP SWITCH CONNECTED IN SERIES WITH SAID LAMP AND A SOURCE OF POWER, SAID SWITCH BEING NORMALLY OPEN BUT BEING ADAPTED TO BE CLOSED BY SAID SOLENOID, MEANS TO APPLY VOLTAGE ACROSS SAID SOLENOID FOR A TIME SLIGHTLY GREATER THAN ONE ROTATION OF SAID ROLLERS, AND MEANS OPERATED SAID ROLLERS TO REACTIVATE SAID VOLTAGE APPLYING MEANS ONCE EACH CYCLE OF SAID ROLLERS. 